Detailed definition
Multiple observational studies — notably the Million Women Study and the Collaborative Group on Epidemiological Studies of Ovarian Cancer pooled analysis — have suggested a small absolute increase in ovarian cancer incidence with long-term HRT use, particularly with use beyond 5–10 years. The Collaborative Group analysis estimated approximately 1 additional ovarian cancer per 1,000 women on HRT for 5 years. The mechanism is unclear; increased ovulation cycles cannot be the cause in postmenopausal women. WHI did not show a statistically significant increase in ovarian cancer in either arm. Major societies discuss this as a small risk that should be considered in long-duration HRT decisions, while noting that the absolute risk remains low and overall mortality is not increased.
Why it matters in menopause
Ovarian cancer risk is one of the considerations in long-duration HRT decisions but is rarely the dominant factor. For women with strong family history or BRCA mutations, ovarian cancer risk is a separate larger conversation that includes risk-reducing surgery options.
Related terms
Sources
External references: Wikipedia.